Possibility of $T_{c\bar{s}}(2900)$ as the resonance-like structure induced by threshold effects

We investigate the process $B\to \bar{D}{D}_s\pi$ via several rescattering processes. It is shown that the triangle singularity (TS) peak around the $D^{\ast }{K}^{\ast }$ threshold generated from the ${\chi }_{c1}{K}^{\ast }{D}^{\ast }$ loop is relatively narrow, which may simulate the resonance-like structure $T_{c\bar{s}}(2900)$ recently observed by LHCb in the $D_s\pi$ spectrum. However, the TS peak around the $D_s^{\ast }\rho$ threshold generated from the $D^{\ast \ast }{D}_s^{\ast }\rho$ loop is smoothed by the broad width of $\rho$, which itself can hardly describe the $T_{c\bar{s}}(2900)$ structure. A TS signal around the $DK$ threshold generated from the ${\chi }_{c0}KD$ loop is also predicted.